Switch construction



G. R. RUNKE SIITCH GONSTRUG'HQN Aug. 17, 1948.

Filed lay 21. 1943 I 3 Sheets-Shoot 1 Maui/01v IN V EN TOR. 611m! A.flaw/m 17, 1943- I G. R. RUNKE 2,447,137

SWITCH CONSTRUCTION Filed May 21, 1945 3 Sheets-Sheet 3 Patented Aug.17, 1948 SWITCH CONSTRUCTION Glenn R; Runke, Racine, Wls., aasignor toLine Material Company, South Milwaukee, Win, a

corporation of Delaware Application May 21, 1943, Serial No. 487,883

This invention relates to a switch construction. -'In greater detail,this invention relates primarily to aswitch construction of the circuitbreaker type.

Objects of this invention are to provide a circuit breaker which has aquick make and a quick break, which has condition responsive means ofthe trip type, which is so constructed that it releases the circuitbreaker so that the circuit breaker will open under predeterminedconditions, and which is provided with a handle or other operating meansfor normally opening and closing the circuit breaker and for resettingthe trip means, the trip means and the operating means being so relatedthat the trip means will operate to release the circuit breakerirrespective of the position of the operating means and irrespective 01'any motion that the operating means may be executing at the time thetrip means operates so that the trip means 'is trip free and willoperate no matter whether the operating means is forcibly held in closedposition or is being moved from one position to another.

Further objects are to provide a circuit breaker which is so constructedthat the circuit breaker cannot be closed until the trip means has movedback to normal position, and in which the resetting of the trip means isaccomplished by moving the operating means towards openposition, suchmotion being followed by movement to closed position after the resettingof the trip means when it is desired to again close the circuit breakerafter the occurrence of the predetermined condition.

Further objects are to provide a construction in which the trip meansmay be either thermostatically or magnetically or otherwise operated andwhich has either a quick action or a delayed action and which isadjustable so that the condition to which vit will respond may bepredetermined.

Further objects are to provide a circuit breaker which has a heavycontact pressure when it is the parts during the opening and closing ofthe circuit breaker or during the resetting of the trip 2 means as themechanism is so arranged that during resetting, for example, relativelysmall forces or pressures are exerted between the cooperating parts,thereby minimizing wear.

Further objects are to provide a circuit breaker in which the trip meansis required to exert only a very small force in order to cause automaticoperation, the relation of the parts insuring relatching without anychance of wedging or jamming either the trip mechanism as a whole or anyportion of the latch means.

In circuit breakers of the toggle link type, as heretofore constructed,it has been a common practice to pivot one end of the toggle linkmechanism at one point and deliver the force due to the toggle actionfrom the other pivoted end of the toggle link mechanism. This oldarrangement produced a true toggle action.

Further objects of this invention are to provide a switch which may beof the circuit breaker type with mechanism which includes a air ofmembers pivoted together with the outer end of one of the memberspivoted at one point and with the other member constituting a followerand mounted so that it is merely guided and arranged to carry themovable contact, and to so organize and arrange the mechanism that thereis no toggle action until the movable contact engages a stationarycontact and to have yielding means for one of the contacts.

Further objects are to provide a circuit breaker which does not requirethe collapse of a toggle mechanism when it is automatically released, ason overload for instance, but in which a follower is suddenly directlypulled by spring means away irom'the stationary contact to therebysecure a very'quick break so that the speed with which the contacts areseparated, even at the initial portion of the movement of separation, isgreater than that which would have been provided by the collapse of atoggle mechanism arrangement.

Further objects are to provide a circuit breaker construction whichissturdy and is reliable in operation, which may be installed in atransformer case and submerged in the oil in the transformer case ifdesired, and which if a thermostatic trip means is employed, may bearranged to have the thermostatic means respond solely to the heatgenerated by current passing through the thermostatic means or to thecombined action of the heat in the oil from the transformer or otherdevice as well as from the heat due to the current passing through thethermostatic means, or may be arranged to respond solely to the heat ofthe oil.

Embodiments of this invention are shown in the accompanying drawings, inwhich:

Figure 1 is a sectional view through the circuit breaker, such viewcorresponding approximately to a section on the line of Figure 2 andshowing the circuit breaker in closed position, one of the upper linksbeing sectioned off.

Figure 2 is a plan view of the circuit breaker with a part of the mainoperating means sectioned oil.

Figure 3 is a view corresponding to Figure 1 showing the circuit breakerafter it has been manually opened.

Figure 4 is a view corresponding approximately to Figure 1 showing thecircuit breaker after it has been automatically opened, such view.however, having parts broken away and having both of the upper linksshown.

Figure 5 is a fragmentary detail showing the thermostatic means.

Figure 6 is a view showing the circuit breaker mounted in a transformercasing.

Figure '7 is a sectional view onthe line 1-1 of Figure 6.

Figure 8 is a view showing another manner in which the circuit breakermay be mounted.

Figure 9 is a wiring diagram.

- Figure 10 is a view of a further form of condition responsive means.

Before proceeding with the detailed description of this invention it isto be understood that the circuit breaker may have either a singleswitch means or a plurality of switch means, a circuit breaker with asingle switch means having been chosen for the sake of illustration.

Referring to the drawings, it will be seen that the circuit breakercomprises an insulatin body portion which has a base I and a pair ofinsulating upstanding walls 2 carried thereby. Between these walls afloating follower 3is provided which is preferably formed of two spaced,generally triangularly shaped plates integrally joined by a transverselower web 4 and also joined by a transverse upper web. 5. Each side wallof the follower or member 3 is provided with an elongated slot6 which isslidably guided by means of a pin 8 supported from the walls 2 andprovided with a roller 1, so that the follower 3 may rock about the pin8 or may have translatory motion with or without rocking, therebyconstituting the follower a floating member.

A movable contact 9 is slidable through an the links and the side wallsof the follower For the sake of clearness one of the links has beensectioned oil in both Figures 1 and 3.

Main operating means in the form of a pair of levers 2| are pivoted onthe pins 22 carried by the side walls 2 and are located on oppositesides of the channel-shaped floating follower 3. They are Joined attheir upper ends by means of a transverse pin 2-3. The main operatinglevers or means 2| are operated in any suitable manner. For example,they may be operated by means of insulating links 24 connected t rockarms 25. The rock arms 25 are rlgidlymounted upon a rock shaft 26, seeFigures 6 and 7, and the shaft 26 extends through the casing 21 of thetransformer 28 and is provided with an operating handle 29 locatedexternally of the transformer. This main operating means consisting ofthe levers 2| is adapted to be rocked from the full line position shownin Figure 1 to the dotted line position for opening the circuit breakerand is adapted to be rocked in the reverse direction for closing thecircuit breaker, the closed position being shown in Figure 1 and themanually opened position being shown in Figure 3. A pin 30 is secured tothe levers 2| and carries a reset roller or sleeve 3| whose purpose willhereinafter appear. Springs 32 extend between the pin 30 and the pin I9and are always under tension. The ends of the springs 32 may be attachedto members 3|! and I9 through which the pins 30 and I3, respectively,pass. These springs are located on opposite sides of the carrier M. Itis to be noted that the carrier I4 is provided with a cam surface 33which not only acts as a cam in a manner hereinafter to appear, but alsoacts as a stop, the sleeve or roller 3| engaging such surface as shownin dotted lines in Figure 1 and in full lines in Figure 3 to arrest thecounterclockwise motion aperture in the transverse web 4 and is springis provided wtih a terminal member i3. Obviously the contact 9 could berigidly mounted on the follower and the contact i2 could be yieldinglysupported.

A carrier I4 is mounted in spaced relation to the floating follower 3and is pivot-ally mounted on a transverse pin i5, suitable spacersleeves l6 being carried by the pin l5 to hold the carrier ll centrallybetween the walls 2 of the body portion.

An upper link structure H, which may be composed of a pair of separatelinks located on each side of the carrier It, is pivoted on the pin |8to the carrier M and is pivoted by means of a pin as indicated at I!) tothe floating follower '3. Suitable spacer sleeves 2|! are carried by thepin l9 and positioned between the links H, and between of the mainoperating means 2| when the circuit breaker is manually opened. I

From the description thus far given it is apparent that when the mainoperating means 2| is rocked from the full line position shown in Figure1 towards the dotted line position shown in Figure 1, which is the fullline position shown in Figure 3, the line of pull of the springs willpass a line joining the center of the pins l8 and i9. When it has passedto the left beyond such line, it will pull the pivoted link l1 suddenlyto the left, thus causing the circuit breaker to move to open positionwith a sudden motion, the manually opened position being shown in Figure3.

During this operation it is necessary for the pivoted link to slightlyfurther compress the relatively heavy spring l0 and a considerableamount of energy is stored not only in the springs 32 but also in thespring Ill, all of which springs are effective during the actual openingmotion of the circuit breaker, the effect of the spring l0 assisting ininitiating the opening and the eifect of the springs 32 continuingthroughout the entire opening stroke.

A slight sliding motion occurs between the floating follower 3 and theguiding pin 8.

When the main operating means 2| i rocked to the right from the fullline position shown in Figure 3, it is apparent that when the line ofpull of the springs 32 passes beyond .the line joining the center of thepins l9 and IS. the mechanism composed of the pivoted link H and thefloating follower 3 will suddenly rock to the right and close the switchwith a quick action, slightly compressing the relatively heavy spring inand caus- 5 ing a slight sliding action to occur between the floatingfollower 3 and the guiding pin 3.

A peculiar action is to be noted at this point. Heretofore in togglelink mechanisms it is the usual practice to transmit the force from thepivoted end of one of the links of the toggle mechanism. In theconstruction forming the subject matter of this invention, it is to benoted that the follower 3 is a floating follower and merely floats withreference to the guiding pin 9. There is no toggle action whatsoever inthe mechanism hereinabove described until the contacts are in actualengagement and then the toggle action is between the links l1, a portionof the floating follower 3 and the spring l3 and the movable contact 9bearing against the stationary contact If. During this portion of itsoperation the spring II is compressed and the movable contact 9approaches nearer to the transverse member 5 than in the open position.Thus the effective arm, composed of a portion of the followe 3, thespring I and the movable contact 9, constitutes at most one link of atoggle link mechanism while the contacts are in actual engagement andsuch effective link shortens during the flnal portion of the closingmotion of the circuit breaker.

It is to be noted that the follower '3 has both motion of translationand motion of rotation.

Motion to the right of the link |1 when the switch is in closed positionis limited by engagement between the link l1 and the spacers I9 carriedby the pin i5. From an examination of Figure l it'is apparent that theaxis of the pin l9 has moved slightly to the right of a line joining thecenter of the movablecontact 9 and the pin 18 and consequently themechanism tends to lock in this position as the line of pull of thesprings 32 is to the right as viewed in Figure 1.

Means are provided for automatically opening the circuit breaker uponthe occurrence of a predetermined condition, such for example asoverload. This is accomplished by providing condition responsive means,such as the thermal e1.- ment 34 which may be of inverted U-shape asshown in Figure and which is provided with an upper insulating headportion '35 through which an adjusting screw 36 is" threaded, such screwbeing provided with an insulating pin 31 adapted to release tripmechanism in a manner hereinafter to appear.

The flexible leader H is connected to one leg of the thermal element 34and the terminal 38 is connected to the other leg of the thermalelement. The thermal element is adapted to warp to the right as viewedin Figure -1 upon overload. The thermal element 34 may be of the commonbimetallic type.

The latch mechanism may comprise a main latching lever 39, see Figure 1,which is pivoted on the pin 49 and is urged in a counterclockwisedirection by means of the spring 4|, a stop pin 42 being provided tolimit the motion of the main latch lever 39 when released. The mainlatch lever is composed of two side members integrally joined by atransverse portion 43. It is provided with a latching pin 44 whichengages the flat upper face of a latching lip 45 integral with thecarrier |4, it being noted that such lip is provided with a roundedlower portion which is adapted to engage a transverse portion 46 of themain latching lever 39 in a manner and undervconditions hereinafter toappear. Normally the main latch lever 39 is held in latched condition bymeans of an auxiliary latching lever 41 which is pivoted on the pin 49and is spring urged 6 in a counterclockwise direction. It is providedwith a pair of lower latching lips 49 which latch beneath the transverseportion 43 of the main latching lever and is provided with a transverseupper portion 50 against which the insulating portion or pin 31 of theadjusting screw is adapted to bear.

pin 49 of the main latch lever and that the point of contact between thetransverse portion 43 of the main" latching lever and the latching lips49 of the auxiliary lever is substantially vertically directly below thepivot pin 48 of the auxiliary latching lever. Thus frictional binding isminimized and a very small force is required to be exerted by thethermal element in orderto trip the compound latching mechanism.

When an overload occurs, the thermal element 34 warps to the right tothe position shown in Figure 4 and releases the main latch lever fromthe auxiliary latching lever, which in turn releases the carrier M fromthe main latch lever. The carrier suddenly rocks upwardly and thefollower 3 is suddenly jerked upwardly by means of the springs 32, theinitial portion of the upward motion being assisted by the spring Hi.There is a slight rocking of the follower 3 due to the action of thelink H but therelease is primarily due to the direct upward motion ofthe follower 3. It will be seen that the floating follower 3 slides aconsiderable distance with reference to the guiding pin 8 during thisupward motion upon comparing Figures 1 and 4.

It is to be noted that the main operating mem-' ber 2| has rocked fromthe position shown in Figure 1 to the indicating position shown inFigure 4,- thus indicating that the circuit breaker has automaticallyopened.

When it is desired to reset the circuit breaker, the main operatingmeans 2| is rocked from the position shown in Figure 4 to the left andthe sleeve or roller 3| rides upon the slanting cam face 33 of thecarrier and forces the carrier downwardly. The carrier is forceddownwardly slightly beyond the position shown in Figure 1 and therounded lower face of the lip 45 of the carrier engages the transversefinger 48 of the main latching lever 39 and rocks such lever to aposition where it will be latched by the auxiliary latching lever 41.Thereafter the main operating means 2| is allowed to move slightly tothe right and the carrier rises and its lip 45 latches beneath the pin44 as shown in Figure 1.

No binding or wedging of the latch mechanism and no undue stressing ofthe thermal element can occur as the portion 43 of the main latch levernever leaves contact with the auxiliary latch lever 41 and clockwisemotion of the main lever 39 does not impose any strain on the auxiliarylatch lever 41. Obviously if the thermal element has not cooled, it willnot be distorted even'if it is attempted to close the circuit breaker,

The circuit breaker may be mounted directly upon the transformer 29, asshown in Figure 6, and may be operated by means of the externallylocated handle 29, see Figure 7, as previously described. The circuitbreaker may be mounted below the oil level indicated at 5| in Figure 6so that the switch is operated in oil and so that the thermostaticelement may be heated not only by the current passing therethrough butby the general temperature of the oil. The purpose of this is to allowthe thermostatic element to respond not only to a relatively suddenoverload but to perature of the oil which would result from a small andprolonged overload due to the heating of the transformer itself. Thusthere may be affordedthe double protection of opening of the switchunder the influence of an overload of reasonable magnitude or theopening of the switch from a prolonged small overload due to the heatingof the transformer. It is obvious also that if desired the main currentneed not pass through the thermal member and the thermal member couldthen respond merely to the heat of the oil if so desired or the oillevel could be so regulated that it is below the thermal member and thenthe thermal member would respond merely to the heat from the currentpassing therethrough.

The circuit breaker is also adapted for wall mounting. For example itmay be mounted within a casing 52, as shown in Figure 8, and aninsulating handle 53- may extend through the curved wall of the casingand may be directly attached to the operating member 2!, whichcorresponds to the operating member 2i hereinbefore described.

Figure 9 shows .a wiring diagram in which the circuit breaker contactsI2 and 9 and the thermal element 34 are connected in series with thesecondary 54 of the transformer 28.

Obviously other forms of condition responsive means may be employed. Forinstance a solenoid type of condition responsive means is shown inFigure in which the solenoid 55 is adapted to raise the plunger 56 tothereby operate the bell crank lever 51 and move the adjusting screw 58s pivotally mounted follower operatively connected to a movable contact,a co-operating contact adapted to be engaged and disengaged by said intocontact with the auxiliary trip lever in the same manner as thathereinbefore described.

It is to be understood that the expression "condition responsive meansincludes not only the thermostatic member shown but also the associatedlevers or latch mechanism.

Any suitable form of time delay means may be provided such as the piston59 connected to the plunger 56 and mounted within the cylinder 60,suitable apertures being provided in the cylinder for the fluid and asuitable sprin 6| being provided for returning the plunger to itslowermost position. The purpose of the time delay is to prevent thecircuit breaker from suddenly opening for any sudden and extremelytransitory overload for instance, but to allow th circuit breaker toopen as promptly as desired for an overload for a period longer thanthat forwhich the time delay has been designed.

It is apparentthat the value of the condition to which the circuitbreaker may respond may be determined by the setting of the adjustingscrews 36, Figure 1, or 58, Figure 10.

Other time delay means of course could be employed and it is to bedistinctly understood that the circuit breaker could be made to respondto over or under voltage, overload, phase reversal, or any other desiredcondition.

The circuit breaker chosen for illustration is a single switch unit typebut obviously, as hereinbefore stated, the circuit breaker may be eithera single or multiple switch type without departing from the spirit ofthis invention.

Although this invention has been described in considerable detail, it isto be understood that such description is intended as illustrativerather than limiting, as the invention may be variously embodied and isto be interpreted as claimed,

I claim: v

1. A switch construction comprisin a floating,

movable contact, a link having one end pivoted to said follower andhaving the other end pivoted at a point spaced from said follower, andmain operating means for rocking said link, said link and said floatingfollower having a toggle action only when said contacts are inengagement.

2. A switch construction comprising a floating, pivotally mountedfollower operatively connected to a movable contact, a cooperatingcontact adapted to be engaged and disengaged by said movable contact, alink having one end pivoted to said follower and having the other endpivoted at a point spaced from said follower, main operating means, andspring means operatively joining said link and said main operating meansfor rocking said link when said main operating means is moved, said linkand said floating follower having a toggle action only when saidcontacts are in engagement.

3. A switch construction comprising a floating, pivotally mountedfollower operatively connected to a movable contact, a, cooperatingcontact adapted to be engaged and disengaged by said movable contact, alink having one end pivoted to said follower and having the other endpivoted at a point spaced from said follower, main operating means, andspring means operatively joining said link and said main operating meansfor rocking said link when said main operating means is moved, said linkand said floating follower having a toggle action only when saidcontacts are in engagement, the line of thrust when said toggle actionoccurs extending directly from the spaced point through said contacts.

4. A switch construction comprising a floating follower operativelyconnected to a movable contact, a cooperating contact adapted to beengaged and disengaged by said movable contact, a link having one endpivoted to said follower and having the other end pivoted at a pointspaced from said follower, means for guiding said follower and allowingboth rotational and translatory motion of said follower, and mainoperating means for rocking said link, said link and said floatingfollower having a toggle action only when said contacts are inengagement, the line of thrust when said contacts are in engagementextending directly through said contacts.

5. A switch construction comprising a floating follower operativeconnected to a movable contact, a cooperating contact adapted to beengaged and disengaged by said movable contact, a link having one endpivoted to said follower and having the other end pivoted at a, pointspaced from said follower, said follower having a slot, guiding meansextending through said slot, and main 0D- rating means for rocking saidlink, said link and said floating follower having a toggle action onlywhen said contacts are in engagement, the line of thrust when saidcontacts are in engagement extending directly through said contacts.

6. A switch construction comprising a floating, pivotally mountedfollower operatively connected to a movable contact, a cooperatingcontact adapted to be engaged and disengaged by said movable contact, alink having one end pivoted to said follower and having the other endpivoted at a point spaced from said follower, and main operating meansfor rocking said link, said link and said floating follower having atoggleaction only when said contacts are in engagement, the li e ofthrust when said contacts are in engagement 9 extending directly throughsaid contacts, one of said contacts being yielding.

7. A switch construction comprising a floating, pivotally mountedfollower, a movable contact yieldingly carried by said floatingfollower, a cooperating contact adapted to be engaged and disengaged bysaid movable contact, a link havin one end pivoted to said follower andhaving the other end pivoted at a point spaced from said follower, mainoperating means for rocking said link back and forth across a linejoining the spaced point and the said cooperating contact, said link andsaid floating follower having a toggle action only when said contactsare in engagement.

8. A switch construction comprising a floating, pivotally mountedfollower, a movable contact yieldingly carried by said floatingfollower, a cooperating contact adapted to be engaged and disengaged bysaid movable contact, a link having one end pivoted to said follower andhaving the other end pivoted at a point spaced from said follower, mainoperating means for rocking said link back and forth across a linejoining the spaced point and the said cooperating contact, said link andsaid floating follower having a toggle action only when said contactsare in engagement, the line of thrust when said toggle action occursextending directly from the spaced point through said contacts.

9. A switch construction comprising a stationary contact, a floating,pivotally mounted follower, a movable contact carried by said floatingfollower, spring means carried by said floating fo1- lower and urgingsaid movable contact outwardly with reference to said floating follower,said movable contact being adapted to engage and disengage saidstationary contact, a link having one end pivoted to said follower andhaving the other end pivoted at a point spaced from said follower, andmain operating means for rocking said link back and forth across a linejoining said stationary contact and the spaced point, said link and saidfloatin follower having a toggle action only when said contacts are inengagement.

10. A circuit breaker comprising a stationary contact, a floatingfollower having a movable contact adapted to engage and disengage saidstationary contact, a movable carrier, condition responsive meansnormally holding said carrier against motion and releasing said carrierupon the occurrence of a predetermined condition, said carrier beingbiased for motion away from said stationary contact, a link pivoted tosaid carrier and to said follower, and main operating means for rockingsaid link back and forth across a line joining the point at which saidlink is pivoted'to said carrier and said stationary contact, said linkand said floating follower having a toggle action on y when saidcontacts are in engagement.

11. A circuit breaker comprising a stationary contact, a floatingfollower having a movable contact adapted to engage and disengage saidstationary contact, a movable carrier, condition responsive meansnormally holding said carrier against motion and releasing said carrierupon the occurrence of a predetermined condition, said carrier beingbiased for motion away from said stationary contact, a link pivoted tosaid carrier and to said follower, and main operating means for rockingsaid link back and forth across a line joining the point at which saidlink is pivoted to said carrier and said stationary contact, said linkand said floating follower having a toggle action only when saidcontacts and in engagement, the line of thrust when said contacts areinengagement extending directly through said contacts.

12. A circuit breaker comprising a stationary contact, a floatingfollower, a movable contact yieldingly carried by said floating followerand adapted to engage and disengage said stationary contact, a movablecarrier mounted in spaced relation to said floating follower and biasedtowards motion in a direction outwardly from said floating follower,condition responsive means normally holding said carrier against motionand releasing said carrier upon the occurrence of a predeterminedcondition, a link having one end pivoted to said follower and having theother end pivoted to said carrier, and main operating means for rockingsaid link back and forth, said link and said floating follower having atoggle action only when said contacts are in engagement.

yieldingly carried by said floating follower and adapted to engage anddisengage said stationary contact, a movable carrier mounted in spacedrelation to said floating follower and biased towards motion in adirection outwardly from said floating follower, condition responsivemeans normally holding said carrier against motion and releasing saidcarrier upon the occurence of a predetermined condition, a link havingone end pivoted to said follower and having the other end pivoted tosaid carrier, and main operating means for rocking said link back andforth, said link and said floating follower having a toggle action onlywhen said contacts are in engagement, the line of thrust when saidtoggle action occurs extending directly from the point at which saidlink is pivoted to said carrier through said contacts.

14. A circuit breaker comprising a stationary contact, a floatingfollower, a movable contact yieldingly carried by said floating followerand adapted to engage and disengage said stationary contact, a movablecarrier mounted in spaced relation to said floating follower and biasedtowards motion in a direction outwardly from said floating follower,condition responsive means normally holding said carrier against motionand releasing said carrier upon the occurrence of a predeterminedcondition, a link having one end pivoted to said follower at a pointflxed with relation to said follower andhaving the other end pivoted tosaid carrier, and main operating means for rocking said link back andforth, said link and said floating follower having a toggle action onlywhen said contacts are in engagement.

15. A circuit breaker comprising a stationary contact, a floatingfollower, a movable contact yieldingly carried by said floating followerand adapted to engage and disengage said stationary contact, a movablecarrier mounted in spaced relation to said floating follower and biasedtowards motion in a direction outwardly from said floating follower,condition responsive means normally holding said carrier against motionand releasing said carrier upon the occurrence of a predeterminedcondition, a link having one end pivoted to said follower at a pointfixed with relation to said follower and having the other end pivoted tosaid carrier, and main operating means for rocking said link back andforth, said l k and said floating follower having a toggle 11 actiononly when said contacts are in engagement, the line of thrust when saidtoggle action occurs extending directly from the point at which saidlink is pivoted to said carrier through said contacts.

16. A circuit breaker comprising a stationary contact. a floatingfollower, a movable contact carried by said floating follower, springmeans carriedby said floating follower and urging said movable contactoutwardly with reference to said floating follower, said movable contactbeing adapted to engage and disengage said stationary contact, a movablecarrier mounted in spaced relation to said floating follower and biasedtowards motion in a direction outwardly away from said floatingfollower, condition responsive means normally holding said carrieragainst motion and releasing said carrier for motion upon the occurrenceof a predetermined condition, a link pivoted to said carrier and pivotedto said floating follower, and main operating means for rocking saidlink back and forth across a line joining said stationary contact andthe point at which said link is pivoted to said carrier, said link andsaid-floating follower having a toggle action only when said contactsare in engagemerit;

1'1. A circuit breaker comprising a stationary said floating followerand said main operating means moving to an indicating position under theinfluence of said spring means upon the release of said carrier.

movable main operating means, and spring means joining said mainoperating means and said link 18. A switch construction comprising afloating follower operatively connected to a movable contact, acooperating contact adapted to be engaged and disengaged by said movablecontact, a link having one end pivoted to said follower and having theother end pivoted at a point spaced from said follower, and mainoperating means for rocking said link about said spaced point withoutcausing motion of said spaced point, said link and said floatingfollower having a toggle action only when said contacts are inengagement.

GLENN R. RUNKE.

REFERENCES crran The following references are of record in the flle ofthis patent:

UNITED STATES PATENTS Number Name Date 1,834,550 Reed Dec. 1, 19311,866,594 Elliott et al July 12, 1932 2,148,295 Hays Feb. 21, 19392,150,013 Von Hoorn Mar. 7, 1939

